Question: If $a + b + c = -4$ and $x + y = 5$, what is $9x - 8c - 8b - 8a + 9y$ ?
Answer: $= -8a - 8b - 8c + 9x + 9y$ $= (-8) \cdot (a + b + c) + (9) \cdot (x + y)$ $= (-8) \cdot (-4) + (9) \cdot (5)$ $= 32 + 45$ $= 77$